class: inverse, middle, left background-image: url(data:image/png;base64,#laseminverse.png) background-position:5% 95% background-size: 50% ## Thigh muscle strength is not related to <br> self-reported function in the medium to long term after anterior cruciate ligament reconstruction .font70[**Michael Girdwood**, Adam Culvenor, Richard Johnston, Ben Mentiplay, Andrea Bruder, Danilo de Oliveira Silva, Tom West, Michael Hedger, Kay Crossley] .pull-left[ .font70[SMA Conference 2022] ] --- background-image: url(data:image/png;base64,#quads2.jpeg) background-size: 120% --- background-image: url(data:image/png;base64,#quads2.jpeg) background-size: 120% .pull-right[ <br> .content-box[ ### What we **don't** know: - In the longer term - is muscle strength related to .red[self-reported function?] - Is muscle strength more important for some people ? - e.g. athletic population 🏃 ] ] --- class: inverse, middle ## Research Question: > - What is the relationship between thigh muscle strength and self-reported function at <u>more than</u> 2 years post ACLR? > > - Is this relationship different in a cohort who run regularly compared to those with ongoing symptoms --- ## Methods - Participants .content-box[ .center[ .font150[n = 120] <br> .font130[ Men and women post-ACLR <br> Aged 18-50 & >2 years post surgery] ] ] .pull-left[ #### <u>Runners</u> - n = 33 - running ≥3x / week - ≥10km / week <img src = "data:image/png;base64,#traillogo.png", width = "50%" /> ] .pull-right[ #### <u>Symptomatic Cohort</u> - n = 87 - 24-36 months post ACLR - KOOS<sub>4</sub> <80/100 <img src = "data:image/png;base64,#superknee.png", width = "70%" /> ] --- ## Methods - Strength Assessment .pull-left[ <br> <br> <br> #### Peak isometric <br>**quadriceps** (knee extension) and **hamstring** (knee flexion) torque ] .pull-right[ <img src = "biodex.jpg", width = "90%"> ] --- ## Methods - Self-reported outcomes #### Knee Osteoarthritis Outcome Score - KOOS .pull-left[ - Pain - Symptoms - Daily Living - Sport & Recreation] .pull-right[ - Quality of Life - Patellofemoral - KOOS<sub>4</sub> - .font70[Average of Pain, Symptoms, Sport & Recreation, Quality of Life subcales] ] <br> #### Data-analysis Beta-regression models modelled the relationship between muscle strength and self-reported function (KOOS subscales). --- ## Results - The Population | Measure | Runners (n = 33) | Symptomatic (n = 87) | |---------|--------------------|-----| |Age (years) | 32 (7) | 31 (6) | |% Female | 36% | 36% | |BMI (kg/m2) | 23.8 (2.8) | 27.9 (5.7) | |Time since surgery (yrs) | 9.2 (7.4) | 2.7 (0.3) | |KOOS<sub>4</sub> | 83.0 (15.9) | 65.6 (12.8) | | Quadriceps Strength (Nm) | 207.5 (54.8) | 184.2 (59.7) | | Hamstring Strength (Nm) | 97.4 (26.3) | 83.1 (29.0) | <br> - The runners had **.black[stronger]** quadriceps and hamstrings, and reported **.black[less symptoms]**. - Time since surgery <u>was not</u> related to muscle strength. --- #### No meaningful relationships between .blue[thigh muscle strength] and .red[self-reported function] .center[ <img src = "ameplot.png" width = 84%> .font70[Findings were consistent for both runners and symptomatic cohorts (no interaction effect).] ] --- ## Results - **.black[Example:]** KOOS<sub>4</sub> Subscale - **10 Nm greater** strength = **0.3% higher** KOOS<sub>4</sub> .font90[(95%CI -0.3 to 0.9%)] .center[ <img src = "scatter.png"> ] --- ## Discussion .pull-left[ - Our findings consistent with most existing literature >2 years post ACLR .font60[(Ericsson 2013; Flosadottir, 2016; Norte, 2018; Moller 2009). ] <br> - Psychological factors could contribute more to longer-term symptomatic outcomes .font60[(Filbay, 2021)]. <br> ] .pull-right[ <br> <img src = "discussion.png" > ] --- class: middle ## Key Summary .content-box[ - .blue[Thigh muscle strength] <u>was not</u> associated with .red[self-reported function] in people >2 years post-surgery - Findings were consistent in a group of runners and a lower functioning symptomatic cohort. - Other non-physical factors may be more important to longer term knee health ] --- class: inverse, middle background-image: url(data:image/png;base64,#team2.png) background-position:15% 58% background-size: 55% .pull-left[ <br> ## Thank you! ] .right[ <br> #### Questions: .font80[ [m.girdwood@latrobe.edu.au](mailto:m.girdwood@latrobe.edu.au) [@m_girdwood](https://twitter.com/m_girdwood) ] ####Slides: <img src = "qr.png" width = 25%> ] <img src = "laseminverse.png", width = 60%>